Trailer construction



Oct. 25, 1938. v c, E, BRADSHAW 2,134,595

TRAILER CONSTRUCTION Filed'Oct. 27, 1936 4 Sheets-Sheet l Oct. 25, 1938. cf E. BRADSHAW TRAILER CONSTRUCTION Filed 0a. 27. 1956 4 Sheets-Sheet 2 (Char Z66 E67 hm,

CZMMMMA Oct. 25, 1938. Q E, BRADSHAW 2,134,595

TRAILER CONSTRUCTION Filed Oct. 27, 1936 4 Sheets-Sheet 3 III Char/65E Brazishaw;

Oct. 25, 1938. cjz. BRADSHAW TRAILER CONSTRUCTION Filed Oct. 27. 1956 4 Sheets-Sheet 4 char lesflfiradshaw Skis 6M Patented Oct. 25, 1938 TRAILER CONSTRUCTION Charles E. Bradshaw, Well ville, Va., assignor of one-third to Charles Martin, Wellville, Va.

Application October 27, 1936, Serial No. 107,873

5"Claims. (Cl. 280-81) This invention relates to vehicle construction and, particularly, to the construction of trailer vehicles.

It has heretofore been customary to attach trailers to their draft vehicle or their so-called tractor by a universal connection whereby the forward end of the trailer will maintain'its equilibrium under ordinary road conditions. The present invention, however, seeks to provide a trailer in which the rear end of the vehicle, as well as the forward end, will substantially maintain its equilibrium under ordinary road conditions.

Another object of the invention is to provide a ground wheel mounting for trailers which will permit the use of a trailer body of increased width without endangering the balance or equilibrium of the vehicle under ordinary running conditions.

A still further object is to provide an auxiliary frame or underframe, supported at its rear end on ground wheels, a substantially universal action being provided between said underframe and wheels, the main frame of the trailer body being yieldingly supported on said underframe. V

A still further object of the invention is to provide a mounting for the ground wheels of the trailer which will minimize lateral stresses im-. posed on said wheels when the direction of travel of the trailer is altered, as when traveling curves or winding roads.

With these and other objects in view, the invention consists in certain details of construction and combinations 'and arrangements of 'parts, all as will hereinafter be more fully. described and the novel features thereof particularly pointed out in the appended claims.

In the accompanying drawings-- Figure l is a side elevational view of a tractor and a trailer connected thereto, the mounting of the trailer body being constructed according to the present invention;

Fig. 2 is a top plan viewof the so-called underframe on which the trailer body is mounted, said View being taken on the line 2--2 of Fig. 1;

Fig. 3 is a bottom plan view of the rear portion of the underframe, illustrating the mounting of the wheels of the truck at the rear of the trailer;

Fig. 4. is a longitudinal vertical sectional view on the line 4+4 of 'Fig. 3;

Fig. 5 is a transverse vertical sectional view'on the line 5*5' of Fig. 3;

Fig. 6 is a detail view illustrating, in perspectiVe, the block on which the trailer wheels are journaled;

Fig. 7 is a side elevational view, partly in section, illustrating a modified form of block on which the wheels are'journaled;

Fig. 8 is a transverse vertical sectional view on the line 8--8 of Fig. '7;

Fig. 9 is a horizontal sectional view on the line 9-9 of Fig. 7, the view being taken looking in r the direction of the arrows;

Fig. 10 is a vertical sectional view on the line m-l0 of Fig. 7; and

Fig. 11 is a detail perspective view illustrating one end portion of the wheel block and the manner in which the axle for one of the Wheels is mounted on said block.

In accordance with the usual practice, the forward end of the trailer body' [0 is connected by a universal coupling, of the ordinary fifth wheel type, to the tractor l I. This universal connection between the trailer and tractor is indicated at l2, and may be of any desired construction, although in the present instance it is shown as being of the type disclosed and claimed in ap plicants Patent No. 2,053,812, dated September 8, 1936. In the present inStance the trailer coinprises a main frame l3 and a supplemental frame composed of articulated sections M, M and which, for convenience, will be referred to as the underframe. It is intended that the main frame 13 and underframe M be capable of moving relativelyto one another. For instance, the front section 14 of'the underframe may be pivoted, as indicated at l5, on brackets l6, dependent from the main frame, and its rear section [4 is supported on ,a truck, on which the ground wheels I l are J'ournaled, The main frame of the trailer is yieldingly supported on the underframe by springs l3, so that one or both sections of the underframe may'move lip-and down independently of the main frame. V t

In order to permit the use of an unusually wide trailerbody and, at the same time, maintain equilibrium of the trailer body, irrespective of road conditions, the rear section w of the underframe is mounted on the whee truck in such fashion as to obtain a more or less universal action just as the forward endof the trailer is mounted for universal movement with respect to the tractor frame. In the preferred form of the invention, the sidemembers of the underframe W are provided with blocks-l9 pivotally supported thereon for rockin motion longi n l y of the frame, and each block is formed with axles 20, 2|, at opposite sides thereof; fore and aft of the pivotal center of the block. Each axle is shown as having one or more ground wheels journaled thereon, but additional wheels may be used on each axle if desired. In this way, the blocks l9 may pivot fore and aft of the trailer body when the wheels encounter irregularities in the roadway over which the trailer is being drawn. The wheel blocks i9 are also adapted to rock, to a limited extent, transversely of the underframe and trailer body. Preferably, the side members of the underframe section M are recessed, as by forming them of laterally spaced angle irons, and the blocks l9 are formed With a flange 22 extending upwardly therefrom into the recesses thus formedbetweentheangle irons. Said flange 22 is formed with an opening through which the pivot pin 23 extends rather loosely and, as will be noted, particularly in Fig. 5, the flange is tapered upwardly so as to provide a clearance between the flange and the angle irons. Therefore, due to the looseness ofthe fit of pivot pin 23 in the apertures of the flanges and the tapering of the flanges themselves, the blocks (9 are free to rock laterally of the vehicle, the degree of rocking being limited to the clearance between the block and angle irons. Referring to Figs. 4 and 6, the upper surface of each block I9 is inclined longitudinally from the center thereof toward its ends and the degree of inclination of these surfaces determines the limit of the rocking movement of the block fore and aft of the trailer. As a consequence, the underframe M, M is mounted on the ground wheels I! at the rear of the trailer, with a substantially universal action, because the blocks l9 .are free to rock both longitudinally and laterally to the underframe and the trailer proper. In addition, this lateral play of the wheel-supporting blocks l9 tends to absorb thrusts that are imposed upon the trailer wheels, when the trailer is traveling curves or winding roads. Also, by the use of dual wheels on each wheel block, the body of the trailer may be made considerably wider and, by reason of the fact that the rocking motions of the wheel blocks are independent of movement of the trailer main frame [3, there is no danger of the body of increased width tipping or losing its equilibrium. That is, by the interpositioning of the springs l8 between the main frame l3 and the underframe, and the ability of the underframe to move relatively to the main frame, the rocking motions of the wheel truck and blocks l9 will have no effect whatever on the balance of the main frame.

In the construction illustrated in Figs. 7 to 11, the wheel blocks l9 are formed with the flange 22 for being pivoted on the underframe section I4, as in the previous construction, but in this modification, the blocks are formed with depending lugs 24 at their opposite ends and each lug is provided with a bearing for a short shaft 25 whose ends project beyond the lugs. The projecting ends 25 of said shaft are of angular cross-section, squared in the present instance, and these squared ends are adapted to receive the axles 20, 2|, the axles being formed with enlarged end portions 26 having square openings 21 therein for mounting on the ends of the shaft 25. In this construction the blocks l9 are capable of rocking fore and aft of the trailer due to the pivotal connection of flange 22 with the underframe, and the wheels by which each block is supported are free to rock as a unit transversely of the trailer by reason of the shaft 25 journaled in the lugs 24. This lateral rocking motion of the shaft 25 and axles 20, 2|, is limited by the surfaces 28 on the enlargements 26 of the axles engaging against the under-surface of the blocks l9, said surface of the block being inclined as at 29 to cooperate with the surface 28.

If desired, means may be provided for guiding the rear end of the carriage underframe in its vertical movements relatively to the main frame I3. For instance, the underframe may be provided with depending bars 30 extending between the angles I l at the rear of the underframe, said bars 30 slidably engaging the underframe whereby the latter may rise and fall with respect to the main frame I3 and be guided by said bars 30.

As before stated, this mounting of the wheels at the rear of the trailer on the underframe and the yielding connection between the rear end of the underframe and main frame together with the pivotal connection between the underframe sections and between the forward end of the underframe and the main frame, insures the body of the trailer proper maintaining its equilibrium under all ordinary road conditions which would otherwise cause a tilting of the rear of the usual trailer. Also, as before pointed out, by having the wheel blocks suspended, so to speak, below the underframe, and providing for the lateral rocking of the wheels, as a unit, with respect to their respective blocks, undue strains on the wheels and the wheel blocks and their connections with the underframe, due to lateral thrust, are eliminated. I

What I claim is:

1. In a trailer vehicle, the combination of a body supporting frame, ground wheels for said body, and a mounting for said ground wheels comprising a truck block mounted directly in said frame, axles projecting from opposite sides of said block, each axle having a wheel journaled thereon, the connection between said frame and said block being such as to permit the blockto rock longitudinally and laterally of said frame.

2. In a trailer vehicle, the combination of a body supporting frame, ground wheels for said body, and a mounting for said ground wheels comprising a truck block, axles projecting from opposite sides of said block, each axle having a wheel journaled thereon, said block being pivotally and loosely attached directly to the frame to permit rocking of said block longitudinally and laterally of the frame.

3. In a trailer vehicle, the combination of the side sill of a body supporting frame, a wheel mounting comprising a block pivotally mounted directly on said side sill to rock fore and aft and laterally of the sill, and ground wheels journaled on said block fore and aft of the pivotal center of the block.

4. In a trailer vehicle, the combination of the side sill of a body supporting frame, said sill having a vertical recess therein, an axle block below said sill, a flange on said block projecting upwardly into said recess, a pivot pin extending through the sill and projection transversely of the sill whereby said block can rock fore and aft of the frame, said block being loosely suspended on said pin and the cross-section of said flange being tapered upwardly whereby said block may tilt transversely of the sill, and ground wheels journaled on said block fore and aft of the pivotal center of the block.

5. In a trailer vehicle, the combination of the side sill of a body supporting frame, an axle block pivoted directly on said sill to rock fore and aft of the frame, a shaft journaled in said block and disposed longitudinally of the frame, axles fixed on said shaft fore and aft of the pivotal center of the block, ground wheels journaled on said axles, and anenlargement on each axle engageable with said block for limiting rotary motion of said shaft in said block.

CHARLES E. BRADSHAW. 

